1. Technical Field
The present invention relates to a semiconductor device wherein semiconductor elements such as transistors etc. are used on a bendable substrate.
2. Related Art
In recent years, the experimental production of bendable display devices, e.g. sheet-type display devices having flexibility such as electronic papers, organic EL displays etc., has been in progress. In such display devices, electric circuits configured of pixels and transistors are formed on a flexible substrate, for example. Transistors are made of semiconductors such as amorphous silicon film, polycrystalline silicon film, monocrystalline silicon film etc., which can be referred to in an example of related art JP-A-9-312349.
When a sheet-type display device is bent for use, however, transistors that have been formed on a flexible substrate in a flat state are slightly deformed with the curvature of the substrate. The deformation has been found to change the characteristics of transistors. The change of transistor characteristics could cause the malfunction of electric circuits formed on a substrate.